Ah, sorry, tab mixup on my end, the quote is from another article linked in the comments below; http://www.lowtechmagazine.com/2014/06/thermal-efficiency-cookin

Ah, sorry, tab mixup on my end, the quote is from another article linked in the comments below; http://www.lowtechmagazine.com/2014/06/thermal-efficiency-cooking-stoves.html http://www.lowtechmagazine.com/2014/06/thermal-efficiency-co... Anyway, the question you pose is a good one.